I upgraded a client on Sage 100 Std 2013 to PU9 and loaded the 2015 IRD. Now when anyone opens SO Data Entry or SO Invoice, and enters a new or existing SO or Invoice, they get an error 88. All other modules seem to be ok. If I switch to a different company, I get the same error. Client does not use any form of credit card processing or CRM. Sage Support seemed to think it might have something to do with a 3rd party app showing up in the MAS90\links folder, although the 3rd party app is actually the GL sync for the last payroll service Sage no longer supports. That app imports a GL entry from the Payroll Service. I have run the customizer utilities, reinstalled WS setup, and run the WS Std Update. Waiting for Sage to research. Does anyone have any ideas where I might look next?